Storage shelves positioned in high places are often inaccessible to certain groups of individuals. For instance, children, the elderly and persons of shorter stature often have difficulty or are unable to reach and retrieve items stored on shelves placed high up in storage devices. Tall hallway closets or wall mounted cabinets positioned above large household appliances pose particularly difficult problems. These individuals must precariously stand on stools, ladders or the like so that they may access the stored items from the upper shelves. This practice is often dangerous, especially for children and the elderly.
Moreover, these problems are magnified for the handicapped where top shelf accessibility is even more remote. When seated in their wheelchair, retrieval of any item outside of their immediate reach is extremely difficult. Hence, most of the middle to upper storage capacity of a storage device is of little use to a handicapped person without additional aid.
In an effort to increase accessibility to the upper shelving of conventional cabinets, particularly of the wall mounted type, storage assemblies may be retrofit with pull down devices which raise or lower the shelves so that these certain groups of individuals can reach or access the stored items. These devices generally include a pantographic framework pivotally mounted to a shelf or shelves which swing the shelves outwardly and downwardly from the upper cabinets to a deployed, lowered, position for more convenient access. Generally, these devices lower the shelves while maintaining an ordinarily level orientation. Typical patented, prior art, pull down retrieval systems set may be found in U.S. Pat. Nos. 5,058,846 to Close; 4,915,461 to Kingsborough et al.; 4,134,629 to Hansen; 4,076,351 to Wyant; 4,026,434 to Howard; 3,347,591 to Soroos et al.; and 159,501 to Cogswell.
While these assemblies may been adequate to permit access of the storage assembly from the raised position, most are deficient for one reason or another. For example, the prior art assemblies do not permit the shelves, once lowered, to be pulled or extended forward for additional access. This motion provides even greater access to the storage shelf because the shelf may be moved clear of the pantographic framework where the shelves are stacked atop one another. This is especially true in multiple shelf assemblies.
In addition, many of the assemblies are inherently complex, requiring an array of pulley and linkage mechanisms, and springs biasing systems necessary to raise and lower the shelves. The Hansen patent, for instance, discloses a pantographic framework having individual link members intercoupled between a wall mounted frame, a pull down shelf, the ceiling and a folding door. This complex linkage assembly, requiring numerous parts, is very difficult to use and assemble.
Other pull down assemblies provide costly and complex mechanisms which facilitate retraction of the deployed, lowered, shelf back to the stored position. The Kingsborough patent employs an electric motor coupled to the pull down linkage mechanism by a flexible cord which draws the lowered shelf back to the stored position. This mechanism is slow to use and must be reversed to deploy the shelf to the lowered position.
The Close, Wyant and Howard patents, on the other hand, disclose pull down storage assemblies including complex pulley mechanisms or spring biasing devices configured to bias the shelf toward the raised position. These prior art assemblies include coiled springs coupled between a stationary fixture, such as a wall mounting frame, and the pull down linkage mechanism. Upon deployment of the shelf to the lowered position, the coiled springs are extended which urge the shelves back to the elevated position. Accordingly, as the user pushes the lowered shelf upward to the elevated position, the spring biased device facilitates upward movement of the shelf.